Truck-body hoist



May l, 1928.

' A. E. HANSEN .TRUCK Bom HoIs'r uw. .i

A. E. HANSENv TRUCK BODY HOIST Filed oct. s. 1925 May l, 1 928.

l Qmwn 14k/'har'. Hansen Patented May l, 192.8.

UNITED STATES 1,668,203V PATENT OFFICE,

ARTHUR E. HANSEN, F SEATTLE, WASHINGTON, ASSIGNOB- T0 YOUNG IRON WOBXB,

0F SEATTLE, WASHINGTON, A CORPORATION 0F WASHINGTON. 'l

TRUCK-BODY HOIST.

body is raised a'nd as the load grows less,

due tothe -increased angle of the dumping y. a Another object is to provide a simple hoist means to be power actuated, as through a hydraulic 'hoist cylinder, Y which Athroll h simple cam means will communicate t e power of the hydraulic hoist to the body to raise the latter.'

Other ollif'ects, and those relating to structural deta' s, can best be ascertained by a study of the following specification and claim, and of the drawings accompanying the same.

Figure 1 is 4in general a side elevation of my hoist, the view being taken substantially along the line 1-1 ofFigure 2.

Figure 2 is a plan view of the hoist ele-A ments, the body and its pivot being omitted so and portions of `the hoist being shown in section.

Figure 3 is -a detail section on line 3-3 of Figu of the In truck hoists, particularly. those horizonal type, heretofore pro sed, so far as I am aware, the power 'of t e horizontal hydraulic hoist cylinder and the cross-head or traveler actuated thereb has been transmitted to the body throng links or levers 40 so arranged that when the maximum lifting effect is required, the mechanical advantage of the levers or linksis the least. When the body is horizontal and it is desired to lift it, most previous ui'iderbod' hoists known Ato 4a me have been so arrange as to give, not the eatest li eect, but the atest speed ig; has been genieally considered necessa due to spare limitations beneath the derbody hoists the body has been `raised farther above the frame or chassis than in the ease of vertical orend hoista* By my invention an extremely simple underbody hoist is provided which ma be u operated from a horimntalhydraulic oist y, though generally vwith uncylinder beneath the body, and which will have the greatest liftingeifect in starting 4to raise the load, and which will increase thespeed of lifting as' the body .rises and as its dead Wei ht load is, in consequence, decreased. 'I us I employ the power of the hoist cylinder to best advantage, and place thereon stresses which are more nearly equalized throughout 'the dumping period, rather than a hi h initial stress to overcome the inertia of t e load and to lift it the lirst few inches, and then a steadily decreasing stress. H

My invention resides in the means which will operate upon an usual type of dumpin body, as l, mounts' upon a suitable truc frame or chassis, as 2, to move it into and from dumping position, as `by pivoting at '10 upon the frame, and which means is actuated to raise the body into, dumping posi- 75 tion through the medium of suitable or usual power mechanism, indicated by the hoist cylinder 3 mounted upon the frame and op` erating a traveler or cross-head 31; particularly my invention resides in the combination ofvsuch means with the body, frame and power mechanism.

The body pivot 10 I have shown as positioned adjacent the rear end of the frame 2 and body 1. The exact form and position of this mounting is largely immaterial, and

it might take a variety of forms' other than o l the straight pivotalconnection illustrated.

It is only. essential that the body be movable relative to the frame 2 by tilting in some manner. 4`Likewise the exact form of the power actuating mechanism is immaterial, and the horizontal hydraulichoist which has been shown as mounted `u n the frame 2 beneath the body 1 is incluoed onl as illustrating a power mechanism Whic is common in the art. Any suitable power mechanism for actuating the traveler or cross head 31 may be employed.

For convenience I have provided a traokl way 21 extending lengthwise of the frame members 2, and have provided trackway' rollers 32 upon o vpositie ends of the cross head, by means o which the cross head or l traveler 31 is permitted a sliding en age- 105 ment and movement lengthwise ofthe ame 2. It will be noted that at each side of theA frame I have provided two'such trackways 21, sli htly separated. A sin letrackway at eac side might prove suient, and it 11g i might be sufficient in some cases to have only one or a pair of these trackways centrally located, but in order to better distribute the load and to balance it, I have provided these trackways and duplicate rollers 32 at each end of the cross head 31. An additional reason for providing such trackways, and for placing them below the level of the upper flange of the frame member 2, as best shown in Figure 3 is to enable the rollers to be of larger diameter than if they ran directly upon the frame members 2. This reduces their angular speed and the friction in their bearings, and prolonge the llife and eiliciency of all such parts. p

By means of the construction so far described, by controlling the movement of fluid within the hydraulic, hoist cylinder 3 in the usual manner, the cross head 31 connected to its piston rod 30 is moved lengthwise the frame 2, the traclrway rollers 32 riding along the rails 21. Preferably the movement of the traveler 31, when it 1s detraveler to raise the body.. Such4 means is.

sired to raise the body 1, is in a direction from the front of'the frame towards the body pivot 10 -at the rear.

I provide means which areinterposed between the traveler 31 as it slides rearwardly along the frame and the body 1, which means is actuated by the movement of the conveniently formed as' a cam. The exact form or manner of connection of this cam ty of the body with the body or with the traveler 31 may be greatly varied. Essentially it constitutes a member having its under surface formed as a cam, generally convexly curved, as indicated at 40, this surface being engaged b the traveler 31, or by a cam roller 34 carried thereon, and this member 4, which has the cam surface 40 formed thereon, being operativel connected to the body so that as the trave er 31 traverses the cam surface 40 and raises it, the body 1 will be raised.

I have found it preferable to form the member 4 as a hoist arm which is pivoted at 42 upon the frame 2 at a point in the vicinivot 10. The free end of the'armA 4 exten s forward from its pivot, and extends suiiciently above the frame 2 or the track 21 secured thereto to permit the roller 34 and the traveler 31 to liev beneath its cam surface 40. Its swinging end has sliding en agement with the under surface of the bo y 1, and may be provided with .a roller 41 traveling upon a trackway 14 on the under surface of the body.

. The conformation of the cam surface 40, in the form just described, wherein it is formed upon a pivoted hoist arm, is largely dependent upon the relative vpositions of the pivot 42 of t and upon the nline of movement of the travel'er 81 with respect to such pivots. In the e hoist'arm and 10 of the body, v

form illustrated in Figure 1 the pivot 42 is somewhat forward of the body pivot 10 and below it, and the line of movement of the traveler 31, if extended, would intersect a line connecting the two pivots 10 and 42. It will be evident that the relative positions of the pivots 10 and 42, and of the line of movement of the traveler 31 relative thereto, may bel varied without departing from the scope of my invention. The two pivot points might coincide, for instance.

It is my object in forming the cam surface 40 to so shape this surface that the initial lifting effect, that required to overcome the inertia of the load and to lift its dead weight until an appreciable angle with the horizontal is made, is the greatest. lThis necessitates, of course, that the speed of lifting or of angular movement of the body 1 be low at the start. However, as the angle of the body 1 increases up to and beyond the normal dumping angle, its load upon the hoist arm or upon the traveler 3l decreases. Hence t is my object to so shape a given angular amount as the dumping" progresses. y

In the form shown in Figure l, which is my present preferred form, when the pivots 42 and 10 and the traveler 31 are located in the relative positions shown, I have found that the body will begin to lift at very slow speed but with a large lifting effect from a given power input to the hoist cylinder 3, and the s eed of lifting will increase gradually as tile traveler 31 or the cam roller 34 travels A alon the cam surface 40. When parts reach t e dotted line position of Figure 1 dumping will ordinarily have occurred. Here the lifting effect is not great, owing to the close approach of the cross head 31 to the pivot 42 of the hoist arm. However, as the load has been dumped and there is only the weight of the empty body 1 resting upon the hoist arm, the hoist cyllnder 3 is at all times capable of sustainin and lifting the load placed 'upon it. In e ect the action of the traveler 31 in lifting the load is as thou h a -wedge were forced alon the frame 2 an between it and a genera ly inclined surface upon the bottom of the body 2.

-It will be understood that the structural details may be varied to suit the ideas of the designer. I have showntwo frame bars and lll izo

two tracks 21 at each side of the truck frame,

as p lainedabove, and have placed the 'arm 4 so it will swing between the trackways 1,eee,aos e between the two trackway rollers 32 althou h all three rollers at each end of the trave er 31 are ivoted upon this trave1er.'

Preferably also t e cam roller 34 is sli htly less in iameter than the two trac way rollers 32, and as the arm 4 rests upon the smaller central roller 34, its sides are enged by the larger` outside rollers 32 to steady it, and totake any Side thrust therefrom and to transmit it direotllyv to the frame 2. This can best be seen 'in igure 3. What I claim as my invention is:

In combination, a truck frame, a dumpivoted thereon, a pair of sepa# ingbody rated tra at each side of the lframe, a

hoist arm pivoted upon the frame and positioned-between each pair of tracks, the free end of saidarms having sliding engagement with the under side'of said body, a power actuated cross-head movable lengthwise of the frame, pairs of traokw'ay rollers thereon movable along said pairs of 4tracks, anda cam roller between each pair of trackway rollers, and of lem diameter, said cam rollers each e ing the under side of a hoist arm and mova le therealong as the cross-headv is moved to raise a vd lower the hoist arm.

Signed at tle, King County, Washington, this 1st day-of October, 1923. y

ARTHUR E. HANSEN. 

